Moth Mutation

Researchers have identified the genetic mutation that famously turned moths black during the industrial revolution.

20:32 03 June 2016

Researchers from the University of Liverpool have identified the genetic mutation responsible for a black form of peppered moth that rapidly took over in industrial parts of the UK.

 

One of the researchers, Dr Ilik Saccher, said: "When I started working on it I was surprised, given how well known it is, that no-one had actually tried to... characterise the underlying genetics controlling the physical appearance of this moth.”

 

"It's a graphic example of rapid evolutionary change. In the days before we could track mutation and change in bacteria and viruses, there weren't many examples of visible change within a human lifetime."

 

To zero in on the gene behind the “industrial melanism”, Dr. Saccheri’s team started with traditional genetic mapping. They then focused their attention on a stretch of the moth genome containing 400,000 bases.

"We knew that within that 400,000 bases, there was some sequence that had to... cause the actual difference between the black type and the typical type," Dr Saccheri explained.

"So we went about an excruciatingly tedious process of identifying every single difference between the two types."

 

"After a long time we eventually managed to get down to a single one, which then had to be the causal mutation. To our surprise, it also turned out to be a rather unusual type of mutation."

 

Prof James Mallet, an expert on butterfly and moth genetics from Harvard University and University College London, described the study as an “incredible piece of work.”

 

"These have been incredibly difficult animals to work with. It's not easy as a lab animal, it's hard to breed - it has one generation a year - and it has really limited polymorphism. So it's very hard to use standard genetic techniques to map the genes and locate them on the chromosomes."